DE10047419A1 - Lancet system - Google Patents

Abstract

The lancet system (1), to take blood samples, has a drive mechanism (6) to move the lancet needle (2) from its rest position into the penetration setting to take blood. The extended needle is retracted (7) by the system into the rest position. The lancet, to take blood samples, has a section which can be gripped by the retractor, at the end away from the lancet needle point (5). The retraction unit has a spring (8) action, in the magazine for the lancets. An Independent claim is included for a lancet magazine, which can have a system to move the lancets from a ready position into the working position to take blood.

Description

The invention relates to a system for storing and providing lancets for Obtaining body fluids, especially for blood collection, as well as a corresponding working method for the system for the purpose of obtaining Body fluids, especially blood collection.

Examination of samples of body fluids, especially blood samples, enables early and reliable detection of. in clinical diagnostics pathological conditions as well as the targeted and well-founded control of body conditions. Medical blood diagnostics always involve taking a blood sample from the investigating individual ahead. While in clinics and with resident doctors often several milliliters of blood from a person to be examined through venipuncture can be obtained for the analysis in order to carry out a large number of laboratory tests are sufficient for individual analyzes that are aimed specifically at a parameter, nowadays often a few microliters of blood or even less. Such a small one Blood amounts do not require venipuncture. Rather, it is sufficient here to obtain blood through the skin e.g. B. in the fingertip or the earlobe of the person to be examined with the aid of a sterile, sharp lancet, so that a few microliters of blood or even gain blood amounts in the nanoliter range for analysis. It is particularly suitable this method when analyzing the blood sample immediately after blood collection can be carried out.

Especially in the area of so-called "home monitoring", that is, wherever medical laypeople perform simple analyzes of the blood yourself, and there in particular for the regular, Blood collection to be carried out several times a day by diabetics for the control of Blood glucose concentration, lancets and matching devices (so-called Blood collection devices, blood lancet devices or lancing devices) are offered, the one enable blood production that is as painless and reproducible as possible. As examples of Lancets and lancing devices are the commercially available devices (lancing devices) and Lancets called Glucolet® from Bayer AG and Softclix® from Roche Diagnostics GmbH.  

Such lancets and devices (lancing devices) are the subject of, for example EP-A 0 565 970.

In the currently commercially available systems, the lancets are provided for the use in lancing devices mostly in loose form. The user removes manually each lancing process a lancet from a package, for example a cardboard box or a tube in which a large number of lancets (mostly disordered, loosely poured) is included. Then the lancing device, for example by unscrewing or Pulling off a cap, prepared for receiving the lancet, using the lancet holder the lancing device is exposed. The lancet removed from the pack is manually inserted into the Lancet holder of the lancing device inserted and fixed there. Then the protective cover of the Lancet can be removed manually. Then the lancing device with its cap closed again. The cap ensures that the lancet is no longer on the outside is accessible. It usually has an opening through which the tip of the lancet actual lancing process can emerge. Finally the lancing device is cocked and stands available for the lancing process to obtain blood.

The multitude of manual operating steps with conventional lancet systems (lancet and lancing device) is perceived by the user as disadvantageous and is especially with limited perception in the state of hypoglycemia problematic. In addition, the user is not prevented from lancing a lancet once inserted once and use blood collection. The multiple use of a lancet has one thing hygienic reasons, especially if more than one person does this Lancet system used, as is the case, for example, in medical practices or hospitals can be or if it can not be excluded that misuse z. B. by Children. On the other hand, the repeated use of the lancets leads to increasing Pain for the user because the lancets are designed for single use they quickly become dull after repeated use. There is also the Lancing devices and lancets of the prior art pose the risk that the lancets improperly inserted into the lancing devices. A user can also log in Incorrectly injuring improper use of lancets and lancing devices.

There is therefore no shortage of attempts to eliminate the disadvantages mentioned. Out Lancing aids are known from US Pat. No. 5,514,152, US Pat. No. 5,152,775, US Pat. No. 4,794,926 and US Pat. No. 5,035,704 stock several lancets and one after the other for lancing processes to be able to use. After the lancing process, the lancets can be removed individually from the device  be removed. The magazine and the possible automated provision of the Lancets help to avoid mistakes when inserting a lancet into a lancing device.

To perform the lancing movement, the lancet must be in the blood collection device (lancing device) first in a lancing direction (that is, with its tip on the one to be pierced Body part) are moved or deflected and then as quickly as possible into their Starting position can be brought back.

In conventional lancet systems, as described for example in EP-A 0 565 970 for this purpose the lancet becomes as solid as possible in its part facing away from the tip enclosed by a lancet holder that is part of the lancing device and both in Lancing direction (forward) as well as moved back to the starting position (backward). The Forward and backward movement is realized by a single drive mechanism, the is often spring-driven.

An automatic lancet change, for example using a Lancet magazine, is with such a system in which an enclosure of the lancet with a lancet holder is difficult to achieve. In addition, the Lancet have a lancet body adapted to the lancet holder, the one establishes a firm connection between lancet and holder, in particular around the Ensure backward movement. The lancets are therefore often voluminous and theirs Storage in a magazine would lead to large dimensions of the lancet system.

The lancet system described in US Pat. No. 4,794,926 uses both the pre-and the Backward movement of the lancet the spring force of a leaf spring, which is part of the lancet. However, this drive concept is not suitable for essentially needle-shaped lancets.

From US 5,578,014 a lancet system is known in which the drive of the lancet for the Forward movement works independently of the drive for the backward movement. The Forward movement is effected by a spring-driven plunger, which is part of a Lancing device is on the lancet from behind, that is, from the tip facing away from it Side, acts. The backward movement is contained by a spring contained in the lancet is driven. Similar systems are described in US 5,029,583 and DE-A 198 55 465. The disadvantage of this variant is that each lancet is equipped with its own spring must, which makes their manufacture complicated and expensive. A miniaturization of the Systems difficult.  

An attempt to reduce the manufacturing costs for such lancets, which are mass-produced items use (so-called disposables), lowering often leads to low-cost Return springs must be used. Often the material properties are in this Fall is subject to large fluctuations, which also causes the return speed is subject to considerable fluctuations. This can negatively affect that Pain sensation during the lancing process.

The object of the invention is therefore to eliminate the disadvantages of the prior art. In particular, it is an object of the present invention to provide a system for collecting blood or other body fluids that have a variety of lancets provides the smallest possible space.

This object is achieved by the subject matter of the invention.

The invention relates to a system for storing and providing lancets for Obtaining a body fluid, in particular for obtaining blood according to claim 1 Method for temporarily extending the tip of an essentially needle-shaped lancet from a system for storing and providing lancets Body fluid, in particular for blood collection according to claim 6, and a Lancet magazine according to claim 8, a lancing device according to claim 12 and a lancet according to claim 13. Preferred embodiments of the invention are characterized by dependent claims defined.

The system according to the invention comprises

• a) a plurality of substantially needle-shaped lancets;
• b) a drive unit which has a drive element, for example a plunger, for Execution of a lancing process is moved from a rest position into a lancing position;
• c) a storage area for storing the lancets;
• d) a removal area for leading at least the tip of a lancet out of the System during the lancing process; and
• e) a transport unit that lancets from the storage area in the Can transport removal area. The drive element is in the invention System arranged so that it is in the removal area to the lancet located there Execution of the lancing process can act, for example, like a hammer or a Firing the firing pin on one end of the lancet and moving it from its rest position into one Lancing position is moved. The system also has a removal area Return device that is in contact with the lancet located in the removal area  can interact to the lancet after performing the lancing of the To move the lancing position to its rest position. The drive unit and the The return device acts independently of one another on the lancet.

The system according to the invention comprises a multiplicity of - that is to say at least two - im essential needle-shaped lancets. "Essentially needle-shaped" means that the lancets have a metal lancet needle with a tip, which if necessary can be sanded. It is important that the lancet itself is not a spring or the like has which it returns to its starting position after the lancing movement. The repatriation the lancet is brought about by a central return device in the system.

For easier handling of the lancet in the system, for example for transporting the Lancet from its storage position to the removal position or for gripping the Lancet through the return device, can be attached to the lancet needle Plastic lancet body made of an injection-molded material. To do that The lancet needle can facilitate gripping of the lancet by the return device its blunt end, i.e. the end facing away from the tip, is also compressed, flanged, kinked or be scored.

The lancet body is usually a plastic component that surrounds the lancet needle is attached and encloses this. The lancet body makes it easier to grip the Lancet needle and can easily be a special, based on the geometry of the lancing device have adapted shape. The outer shape of the lancet is essentially the same Lancet body determined.

The tip of the lancet needle is - when not in use - to ensure it Sterility preferably surrounded by a protective cover. This can be made of the same material like the lancet body, they usually form a unit with it. The Protective cover can be separated from the lancet body and from the lancet body before use The tip of the lancet needle. Between the lancet body and protective cover there is preferably a predetermined breaking point for this purpose.

The lancet of the invention includes a needle (lancet needle) with a tip. The The needle is usually several millimeters (mm) to a few centimeters (cm) long and points an elongated shape. Typically, needles have a cylindrical shape because they are Needle shape is particularly easy to produce; however, there are also needle shapes with different ones Shape possible. The tip area of the needle contains the needle tip, which is used in the  intended use of the lancet is pierced into tissue. The top of the The lancet needle is therefore the part of the lancet that is to be pricked with the skin Individual comes into contact, possibly injuring them and thus the discharge of one Body fluid, especially blood or interstitial fluid.

The tip of the lancet needle can, for example, be rotationally symmetrical, as in FIG Generally the case with sewing needles. However, it has proven to be advantageous if you add one or more cuts to the needle tip. The resulting, for The longitudinal axis of the needle, inclined and tapering at the tip, serves as a needle sharp edge and make the puncturing process less painful than with this rotationally symmetrical needles is the case.

The lancet needle of the lancet according to the invention is made of a material that is sufficiently hard to withstand mechanical stress during the puncturing process Processing steps in their manufacture or any other occurring To withstand stresses without deformation. Furthermore, the material must be like this such that no particles break off or become detached during the puncturing process peel off. Finally, the needle material must also be editable so that the needle tip sufficiently pointed and the edges of the needle point, if necessary, sufficiently sharp can be ground. The most suitable materials for the lancet needle are above all Metals and especially stainless steels. However, there are also ceramic needles, Silicon or plastics conceivable. Stainless steel needles are particularly preferred.

In a preferred embodiment, at least the tip of the lancet needle is the Lancet according to the invention from a plastic body, the following as Lancet body should be called surrounded. It is preferred that the Lancet body in the area of the tip of the lancet needle made of an elastic material consists. At least the tip of the lancet needle is on all sides of this elastic material completely surrounded, that is, embedded in it, and so of the environment completed. The elastic material of the lancet body, which in different Embodiments can completely or only partially form the lancet body is characterized by the fact that it is soft, deformable and from the lancet needle with its tip is penetrable without hurting the tip. The lancet needle is used during the lancing process moves along its longitudinal axis relative to the lancet body and exits with its tip the lancet body in order to collect blood into the skin of the patient to be examined To be able to stab an individual. Another important property is that the  elastic material if necessary when retracting the lancet needle into the The lancet body is closed again around the tip of the lancet needle. After this In a preferred embodiment, the lancing needle can reverse the lancing process the movement during the lancing process is brought into its starting position relative to the lancet body in which the tip is completely covered on all sides by the elastic material of the Lancet body is enclosed.

The elastic material of the lancet body, which is the tip of the lancet needle completely encloses the sterility of the lancet needle tip before it Use, preferably until immediately before their use, and provides for if necessary enclosing the lancet needle tip after use. The elastic material is consequently tight for the penetration of germs. In addition, the elastic material provides a mechanical protection for the lancet needle tip and thus also prevents accidental injury to the lancet needle tip.

As an elastic material for the lancet body of the present embodiment rubber, caoutchouc, silicones, elastomers and in particular thermoplastic elastomers turned out to be suitable. These show the essentials for the present invention Properties on it are soft, deformable, without piercing by the lancet needle injure the tip and they close tightly around the used lancet needle tip. They can also be used for injection molding processes that require mass production of lancets in large quantities.

During the lancing process, the lancet needle is moved relative to the lancet body. The latter is preferably in its position by the lancing device or the lancing device fixed. The lancet needle can be used to drive it forward and / or Backward direction contain suitable elements. In particular, it can be special be shaped, for example a needle head, a flange, a kink or a Have a recess at the end opposite the tip, or in addition to Lancet body, which encloses the tip, have a further lancet body, the can be gripped by the drive element of the lancet system. The shape of the The needle or the additional lancet body can be suitably connected with a corresponding drive device and / or return device in the lancing device (Lancing device) interact.

To increase the stability of the elastic material, it is possible to use a stiff material To connect material, for example a rigid plastic material. The elastic  Material can, for example, on its outside, which is not with the tip of the Lancet needle comes into contact with a layer of a rigid material, for example of a rigid plastic. It is also possible to use the lancet body only in the To produce the area of the lancet needle tip from an elastic material, in the rest Areas to manufacture the lancet body from conventional, rigid plastics. The elastic material and the rigid material can be glued or through an injection molding process, for example a two-component injection molding process, be connected. The rigid material of the lancet body ensures a mechanical stabilization of the elastic material during the lancing process and facilitates the fixation of the elastic part of the lancet body during the Lancing process in the lancet system.

In a further preferred embodiment, the lancet also contains a lancet needle a tip and a hollow body which surrounds at least the tip of the lancet needle, the lancet needle being movable in the region of its tip in the hollow body is and the hollow body is closed by a film that from the tip of the lancet needle can be pierced during the lancing process and which may be after the Retracting the tip of the lancet needle in the hollow body closes again.

Advantageously, this hollow body in the areas that are not with the tip of the Lancet needle come into contact, from a stiff, preferably injection-moldable Made of material.

During the lancing process, the lancet needle is relative to the hollow body, which is the lancet body represents, moves. Holding and driving the lancet needle and fixing the As described above, the lancet body can be designed appropriately will be realized.

The elastic material that forms part of the hollow lancet body is used in the Pierce the lancing process from the lancet needle tip and close if necessary after retracting the lancet needle tip into the hollow body and closes the hollow body. The lancet needle tip is thus sterile until immediately before use The hollow body is sealed and is hygienically enclosed in it after use.

The lancet of this embodiment can be next to the lancet body, which is the tip of the Encloses lancet needle, have a further lancet body, which in the Interaction with suitable elements of a lancing device during the lancing process  this interacts. The lancet needle can also be specially shaped, for example have a head at the end opposite the tip to drive the lancet to facilitate.

In a preferred embodiment, the essentially needle-shaped lancet instructs a needle head at its end opposite the tip. This can be in system interact with the return device, so that the Return the lancet to the starting position after the lancing process (Rest position) can move back. The needle head can - like this for example Pins are the case - be an integral part of the lancet needle. Preferably, the The lancet needle is then made from one piece, in particular from a metal. However, it is it is also possible that the needle head is a separate part connected to the needle, for example a plastic part molded onto the needle. The needle head can be a be flattened, beaded end of the lancet needle, analogously, for example the head of a pin or the face of a nail. Alternatively, the needle head a terminal thickening of the lancet needle or one surrounding the lancet needle and this tightly closing ring or one placed on the blunt end of the needle Be a disc.

The system according to the invention also contains a drive unit for the lancet. The Drive unit contains a drive element, for example a plunger or a hammer, who moves from a rest position into a lancing position to perform a lancing process becomes. The drive element is arranged in the system according to the invention so that it is in the Removal area on the lancet located there to perform the lancing process can act, for example, like a hammer or firing pin on one end of the The lancet strikes, and this moves it from its rest position into a lancing position. It is important in connection with the present invention that the drive unit indeed the forward movement of the lancet causes, that is, the movement which the Brings the lancet from its rest position to the lancing position, but not the cause of it Backward movement of the lancet is. The drive unit can be made in a manner known per se and be configured and, for example, via a spring drive and optionally Have gear elements. Such drive elements are known in principle to the person skilled in the art and can be easily implemented.

Suitable drives are known in many versions from the state of the art. The The drive tappet performs a feed and then a retraction movement.  

During the feed movement, the lancet is also moved forward, that is, into it Lancing direction, moved. This acts during the retraction movement of the drive element no longer on the lancet. This allows the lancet, also one Execute backward movement. Since the lancet according to the invention with a Return device is coupled, this can also the backward movement of the Take over the drive tappet. This is e.g. B. useful if the drive is a simple one Cam is as it is known from valve trains of engines. Even with simple, spring-loaded plungers that snap out of the tensioned position and onto the lancet meet and move them forward, that's possible. In the case of a positively controlled Movement of the drive element, that is, when both the forward and the Return movement of the drive element is realized by a suitable drive, on the other hand, the return device only moves the lancet.

The system according to the invention is used in particular for storage and automated Providing lancets for lancing processes and the execution of the Piercing operations. It therefore also has a storage area for storing the Lancets on. For example, the system can accommodate a room Have lancet magazine. At least the unused ones can be stored in the storage area Lancets are housed. It is preferably also possible to use the ones used there Store lancets until they are disposed of. The system can also be separate Have storage areas for unused and used lancets.

In addition, the system of the present invention allocates an extraction area Lead at least the tip of a lancet out of the system during the Lancing process. To carry out the lancing movement, one is first in the system transported lancet from the storage area to the removal area. The lancet is then in a position in which it is on the one hand from the Drive element of the drive unit in the forward direction, that is, in the direction of Lancing movement, can be driven, and in the other hand with the Return device can interact in a suitable manner to in after the lancing process to be brought back to their starting position. With suitable constructive measures it must be ensured that the lancet is in the removal area with both the drive unit, interact especially with their drive element, as well as with the return device can. Furthermore, the system according to the invention has an opening in the removal area on the emergence of the lancet tip from the system during the lancing process allows.  

As a further component, the system according to the invention has a transport unit which Can transport lancets from the storage area to the removal area. The Transport unit can be driven and / or controlled manually or automatically. The the exact type of transport unit is not essential for the present invention and can depending on the exact type of storage of the lancets in the system. The Transport unit can be driven manually or by means of a spring or a motor his.

Furthermore, the system has a central return device in the removal area, which is connected to the lancet, which is located in the removal area, can interact with the lancet after performing the lancing process from the lancing position to its rest position move. The drive unit and the return device grip independently from each other on the lancet. The return device has a preferred Embodiment a spring mechanism, which is particularly preferably a leaf or Includes coil spring. Alternatively, the return device can be a deformable elastomer have, for example, a compressible rubber block, which when relieved relaxed and thus causes the return movement. Particularly preferred embodiments for the return device and its special interaction with the lancets described in connection with the figures (see below). In contrast to the stand In technology, the system according to the invention has only one central return device; This means that individual lancets do not have a return spring or the like that they follow the execution of the lancing movement back to the starting position.

It goes without saying that the lancets, drive unit and return device of the system according to the invention must be adapted to one another. For example, the lancet can be brought into positive engagement with the return device at least in the reverse direction. This can be done in that the lancet is shaped like a sliding block in a machine tool, which engages in a corresponding T-slot or a simple slot in a sheet (see, for example, FIGS. 1A and 1B, below). The drive mechanism can also be disengaged for the further transport of the lancet, which opens up the possibility of designing the return mechanism as a spring-loaded fork which simply engages behind the thickened end of the lancet (see FIG. 3, below). The slot in the return spring, which is designed as a leaf spring, can also be conically narrowed in the inlet of the lancets and widen again in the outlet, so that the lancet is only a smooth needle, which is clamped on the side in the middle, the narrow point, and thus on the return spring is docked. The blunt tappet of the drive then moves the needle forward, the spring takes it back when the tappet retracts.

The lancets of the system according to the invention are preferred in a lancet magazine accommodated. This can be done after the lancets have been used up from the system removed and replaced by a new magazine. This way the user can of the system simply replace the used lancets with new ones.

The lancet magazine preferably also contains the return device for the lancets. In particular in the event that the return device has a spring mechanism this is an advantage: with every magazine change, the system has a new, unused one Drive spring for the return mechanism available. Fatigue of the Spring material can thus be largely avoided. This makes a consistent one Enables movement execution, which in turn serves to reduce pain when stinging. In addition, in such an embodiment there is no interface between the return direction and the device that holds the lancet magazine. The magazine and thus the entire system containing the magazine can be very compact be constructed.

In addition to a large number of im essential needle-shaped lancets including a storage area for Storage of the lancets and a removal area for taking out at least the Tip of a lancet from the magazine during the lancing process. The magazine points in Removal area either on a return device that is in contact with the lancet Removal area located, can interact with the lancet after execution of the To move the lancing process from the lancing position to its rest position, or leaves the intervention a return device, which is included, for example, in the lancing device. Details of the Individual components of the lancet magazine essentially correspond to the others Said above in connection with the system according to the invention.

A preferred embodiment of the lancet magazine additionally contains one Transport unit, the lancets from the storage area to the removal area can transport. The transport device can preferably be equipped with a corresponding Drive unit in a blood collection device (also referred to here briefly as "lancing device") interact when the magazine is in such a device. In this case the magazine contain part of the drive gear for the transport unit, while in Blood collection device, for example, a drive motor for the transport unit sits. It is  however, it is also possible that the transport unit, in particular its drive motor and its Gearbox, fully seated in the magazine and only its controls and if necessary Energy supply is made from outside the magazine.

Another object of the invention is a lancing device for use in a system for storing and providing lancets for the extraction of body fluids, is particularly suitable for obtaining blood, as described above. As the The system according to the invention comprises the lancing device, a drive unit, a Drive element (for example, a hammer or a plunger), which for Execution of a lancing process is moved from a rest position into a lancing position. The lancing device also has a storage area for storing lancets and a removal area for leading at least the tip of a lancet out of the System during the lancing process. The lancing device also contains one Transport unit, the lancets from the storage area to the removal area can transport. The drive element is arranged so that it is in the removal area the lancet located there can act to carry out the lancing process, and so on is moved from a rest position into a lancing position. The lancing device points in one Embodiment in the removal area on a return device, which with the lancet, located in the removal area, can interact to move the lancet after Execution of the lancing process to move from the lancing position to its rest position. Alternatively, the lancing device can accommodate a lancet magazine described in more detail above, which in turn comprises a return device. The individual elements of the lancing device correspond essentially to the elements of system according to the invention.

The inventive method is used to temporarily extend the tip of a essential needle-shaped lancet from a system for storing and providing Lancets for the extraction of body fluids, in particular for the extraction of blood. It is particularly suitable for the system according to the invention described above. In which The method according to the invention becomes a drive element, for example a tappet, from its Rest position in the direction of his lancing position. It drives a lancet until this has reached its lancing position from its rest position. After the lancet is your Has reached the lancing position, it is returned to its rest position with the aid of a return device recycled. The forward movement of the lancet, that is, its movement out of the Rest position in the lancing position is so by the drive unit, in particular the Drive element causes; the backward movement is caused by the drive unit  independent, separate return device. The return device can In addition to the lancet, also return the drive element to its rest position.

The invention is explained in more detail by the following FIGS. 1 to 3.

Fig. 1 shows a preferred embodiment schematically a detail of the inventive system in which the exchange interaction of the drive element, the lancet and retraction device before the lancing movement (Fig. 1A) and at the end of the puncturing movement (Fig. 1B) is shown.

Fig. 2 shows for a preferred embodiment schematically a perspective, partially cutaway view, in a lancet magazine of the system according to the invention (Fig. 2A) and a corresponding plan view in which the cover of the cartridge housing has been omitted (Fig. 2B).

Fig. 3 shows schematically a further alternative embodiment of the system according to the invention.

FIG. 4 schematically shows, for a further preferred embodiment, a section from the system according to the invention, in which the interaction of the drive element, lancet and return device before the lancing movement ( FIG. 4A) and at the end of the lancing movement ( FIG. 4B) is shown.

Fig. 5 shows a further preferred embodiment schematically a detail of the inventive system in which the exchange interaction of the drive element, the lancet and retraction device before the lancing movement (Fig. 5A) and at the end of the puncturing movement (Fig. 5B) is shown.

Fig. 6 shows a further preferred embodiment schematically a detail of the inventive system in which the exchange interaction of the drive element, the lancet and retraction device before the lancing movement (Fig. 6A) and at the end of the puncturing movement (Fig. 6B) is shown.

FIG. 7 schematically shows a variant of the system from FIG. 6, only the situation before the lancing movement being shown here.

FIG. 8 shows a further variant of the system from FIG. 6, only the situation before the lancing movement being shown here as well.

For a further preferred embodiment, FIG. 9 schematically shows a section of the system according to the invention, in which the interaction of the drive element, lancet and return device before the lancing movement ( FIG. 9A) and at the end of the lancing movement ( FIG. 9B) is shown.

Fig. 10 shows a further preferred embodiment which is to be regarded as a variant of that shown in Fig Auführungsform shown. 9 schematically shows a detail of the inventive system in which the exchange interaction of the drive element, the lancet and retraction device before the lancing movement (Fig. 10A) and at the end of the lancing movement ( FIG. 10B).

For another preferred embodiment, which is to be regarded as a further variant of the embodiment shown in FIG. 9, FIG. 11 schematically shows a section of the system according to the invention, in which the interaction of the drive element, lancet and return device before the lancing movement ( FIG. 11A ) and at the end of the lancing movement ( FIG. 11B).

The numbers and letters in the figures mean

LIST OF REFERENCE NUMBERS

1

lancet

2

Lancet needle

3

Lancet body

4

Lancets head

5

Lancet needle tip

6

driving element

7

retrieval

8th

leaf spring

9

slot

10

Lancet magazine

11

casing

12

guide channel

13

opening

14

fixed part of the return device

7

15

moving part of the return device

7

16

coil spring

17

push rod linkage

18

transport device

19

tilt axis

20

cam

21

Recess in the lancet body

3

22

Crosspieces of the lancet body

3

23

Stop for lancet body

3

24

recess

25

Guide element of the drive element

6

26

guide element
A Direction of movement of the drive element

6

B Direction of movement of the push rod

17

C Direction of movement of the return device

7

when tilting about axis

19

D Direction of movement of the transport device

18

In Fig. 1 a section is shown of a preferred embodiment of the system according to the invention schematically. Fig. 1, the interaction between the lancet (1), the drive member (6) of the drive unit and the retraction device (7) essentially serves to explain. Of the five lancets ( 1 ) shown in FIG. 1, the second lancet from the left is located directly above the drive element ( 6 ). This position marks the removal area of the system according to the invention. The lancet ( 1 ) located there can be driven in this position by the drive element ( 6 ) to carry out the lancing movement. At the same time, the lancet ( 1 ), which is located in the removal area, lies within the slot-shaped recess ( 9 ) of the leaf spring ( 8 ), which is part of the return device ( 7 ).

In addition to the lancet needle ( 2 ), the lancet ( 1 ) contains a lancet body ( 3 ) which envelops the tip ( 5 ) of the lancet needle ( 2 ) before use. At the end of the lancet needle ( 2 ) facing away from the tip ( 5 ), the lancet ( 1 ) contains a lancet head ( 4 ). This and the lancet body ( 3 ) can be injection-molded around the lancet needle ( 2 ) and preferably consist of an injection-moldable plastic. The lancet body ( 3 ) preferably consists of an elastic material, while the lancet head ( 4 ) consists of a rigid material. However, it is possible to form both components of the lancet ( 1 ) from a rigid material.

In Fig. 1A, the lancet (1 '), which is located in the withdrawal area in its rest position. Fig. 1A thus represents the state of the system before or after performing a piercing movement.

In Fig. 1B, the lancet ( 1 '), which is located in the removal area, is in the lancing position. The needle tip (S) is extended from the lancet body ( 3 ). The drive element ( 6 ) acts on the end of the lancet needle ( 2 ) opposite the lancet needle tip ( 5 ). The lancet head ( 4 ) interacts with the leaf spring ( 8 ) of the return device ( 7 ) and stretches it out of its rest position. The slot ( 9 ) of the leaf spring ( 8 ) is wide enough to accommodate the lancet needle ( 2 ). On the other hand, it is narrow enough to provide an area of attack for the lancet head ( 4 ).

As soon as no more force is exerted on the lancet ( 1 ') by the drive element ( 6 ), the leaf spring ( 8 ) of the return device ( 7 ) ensures that the lancet ( 1 '), which is located in the removal area, is returned to its rest position becomes.

The lancet body ( 3 ) is fixed in its position during the lancing movement. This can be done either by the individual lancet bodies ( 3 ) of the different lancets ( 1 ) being directly connected to one another, for example via common connecting webs, or by the lancet bodies ( 3 ) being made of a stiff, band-shaped material which is used here in the Figures are not shown, are fixed. Alternatively, the fixation can be effected by the magazine or its housing.

After performing the lancing movement and returning the lancet needle ( 2 ) to its rest position, the used lancet ( 1 ') is transported from the removal area to the storage area. At the same time, the next lancet (1 ") is moved from the storage area into the removal area.

FIG. 2 shows a possible embodiment for the components of the system according to the invention described in FIG. 1. Fig. 2A is a perspective, partially cutaway view of a lancet magazine (10) into which the elements of the inventive system shown in Fig. 1 are integrated. Fig. 2B shows the same magazine (10) in a schematic plan view, with the upper cover of the lancet magazine housing (11) has been omitted to provide a view into the interior of a magazine (10).

In Fig. 2A, the system is given in the already shown in Fig. 1B state. The drive element ( 6 ) of the drive unit presses from above onto the lancet needle ( 2 ) of the lancet ( 1 ), which is located in the removal area. The lancet needle tip ( 5 ) is pushed out of the lancet body ( 3 ) and the leaf spring ( 8 ) of the return device ( 7 ) is in the stretched state. The magazine ( 10 ) has an opening ( 13 ) in its housing ( 11 ) from which the lancet needle tip ( 5 ) can emerge in order to carry out the lancing process.

As can be seen in particular from FIG. 2B, the interconnected lancets ( 1 ) are moved in a guide channel ( 12 ) of the housing ( 11 ) of the magazine ( 10 ) from the storage area into the removal area and after the lancing movement has been carried out back into the storage area. The individual lancets ( 1 ) are securely shielded from the surroundings by the housing ( 11 ) of the magazine ( 10 ) both before and after the lancing process is carried out.

Since the lancets ( 1 ) can be largely miniaturized, a large number of them can be accommodated in the smallest space. The integration of the return device ( 7 ) in the lancet magazine ( 10 ) ensures that the leaf spring ( 8 ) of the return device ( 7 ) is renewed with each magazine change and thus prevents the material of the return device ( 7 ) from tiring. The magazine also makes it easy and safe to connect the lancing device and lancets.

A further alternative embodiment of the system according to the invention is shown schematically in FIG. 3. Essentially, a plurality of substantially needle-shaped lancets (1), a drive means with the drive element (6), a retraction device (7) and a transport device (18) in Fig. 3 to be seen.

The individual lancets ( 1 ) are connected to one another in the area of their lancet body ( 3 ). In the case shown, the lancet bodies ( 3 ) are applied to a conveyor belt. However, it is also possible for the individual lancet bodies ( 3 ) to be connected to one another via joints or film hinges by touching edges.

Like the lancets from FIG. 1 and FIG. 2, the lancets ( 1 ) from FIG. 3 have a lancet needle ( 2 ) with a lancet needle tip ( 5 ) which is enclosed in the lancet body ( 3 ) in the idle state. To ensure the sterility of the lancet needle tip ( 5 ) before use, the lancet body ( 3 ) can be closed at the top with an elastic material that can be penetrated by the lancet needle tip ( 5 ) (not shown). The lancet head ( 4 ) is located on the side of the lancet needle ( 2 ) facing away from the tip. The lancet head ( 4 ) and the lancet body ( 3 ) are preferably injection molded onto the lancet needle ( 2 ) from an injection moldable material. They can consist of the same or different materials.

One of the lancets ( 1 ) shown in FIG. 3 is located directly above the drive element ( 6 ) and thus in the removal area. The remaining lancets are in the storage area.

In the removal area, the return device ( 7 ) engages the lancet ( 1 ') located there. In the present case, the return device ( 7 ) contains an essentially fixed part ( 14 ) and a movable part ( 15 ). Both parts have a substantially semicircular cutout, which can partially enclose the lancet needle ( 2 ) of the lancet ( 1 ') in the removal area.

If the drive element ( 6 ) is moved upwards in the direction A in order to deflect the lancet ( 1 '), which is in the removal position, from its rest position for lancing, the lancet head ( 4 ) hits the movable part ( 15 ) the return device ( 7 ). When the lancing movement is carried out, the movable part ( 15 ) is displaced against the fixed part ( 14 ) and the coil spring ( 16 ) is thereby compressed. After the lancing movement has been carried out, the drive element ( 6 ) returns in the direction A down to its starting position. The compressed coil spring ( 16 ) of the return device ( 7 ) can now relax and presses the movable part ( 15 ) downwards. The movable part ( 15 ) presses on the lancet head ( 4 ) from above and thus guides the lancet ( 1 ') from the lancing position to its rest position.

The used lancet ( 1 ') can then be transported from the removal area to the storage area. In this case, the right of the used lancet (1 ') lancet located (1 ") - - at the same time a further lancet. Transported from the storage area into the withdrawal area by the thrust rod (17) is moved in the direction B This. Movement means that on the one hand the return device ( 7 ) is tilted about the axis ( 19 ) in direction C (this state is indicated in dashed lines). This tilting movement removes the lancet ( 1 '), which is located in the removal area the return device ( 7 ) is released, ie the parts 14 and 15 are withdrawn by the lancet needle ( 2 ), at the same time the movement of the push rod ( 17 ) in direction B causes the transport device ( 18 ) to turn in direction D. The movement of the Thrust linkage ( 17 ) on the transport device ( 18 ) can take place, for example, via a beveled cam ( 20 ) by the movement of the transport device In the direction D, the next lancet ( 1 ") is transported from the storage area to the removal area and at the same time the used lancet ( 1 ') is transferred from the removal area to the storage area. By moving the push rod ( 17 ) back into its starting position, the return device ( 7 ) is also tilted back and can thus again engage the next lancet ( 1 ) to be used.

FIG. 4 schematically shows a variant of the system according to the invention from FIG. 1. In this variant, the leaf spring ( 8 ) of the return device ( 7 ) is shaped differently, with this design having a similar functionality to the shape shown in FIG. 1 with a simpler design. The partial figure 4A shows the conditions before and after the lancing process; Part 4B shows the situation with the lancet ( 1 ) in the lancing position.

The individual lancets ( 1 ) are further apart from one another in comparison to the embodiment in FIG. 1. The lancet bodies ( 3 ) are connected to one another via connecting webs ( 22 ), which can bring about or support a fixation of the lancets ( 1 ) during the lancing process.

The lancet ( 1 ) in this embodiment contains a lancet body ( 3 ) which surrounds the lancet needle ( 2 ) at two points in the region of its shaft. In alternative embodiments, several locations of the lancet needle ( 2 ) can of course also be enclosed. The blunt end of the needle ( 2 ) can have a molded lancet head ( 4 ) or an equivalent element which is used for coupling to the return device ( 7 ). The needle tip ( 5 ) is embedded in the plastic of the lancet body ( 3 ) to ensure the sterility of the needle tip ( 5 ) until use. Alternatively, the lancet needle tip ( 5 ) can be kept closed in a cavity which is welded on one side with a film (cf. FIG. 3).

The lancet ( 1 ) is constructed in such a way that when the lancet body ( 3 ) is fixed (by lancet magazine ( 10 ) or device), the lancet needle ( 2 ) in the lancet body ( 3 ) can be moved in the lancing direction. In order to make it easier to push the lancet needle ( 2 ) out of the plastic of the lancet body ( 3 ), the needle shaft is kept as smooth as possible at the overmolded points, for example polished. Furthermore, the lancet needle ( 2 ) can be provided with a suitable lubricant in the area of the extrusion coating in order to enable the lancet needle to slide better through the plastic of the lancet body ( 3 ).

By enclosing the shaft of the lancet needle ( 2 ) in at least two places along the needle shaft, the lancet needle ( 2 ) can be positioned exactly axially. The needle shaft is enclosed in such a way that minimal surfaces of the lancet needle ( 2 ) are encapsulated with plastic of the lancet body ( 3 ) in order to achieve the lowest possible frictional resistance (as small as possible less than 1N). The selected plastic should be dimensionally stable so that it does not deform when the lancing movement is carried out. For example, polyethylene or polypropylene have proven to be suitable. The shape stability of the lancet body ( 3 ) and the embedding of the lancet needle ( 2 ) at at least two points ensure that the lancet needle ( 2 ) is guided largely free of play when the lancet body ( 3 ) is fixed and cannot swing laterally. This can reduce pain when stinging.

The drive element ( 6 ) moves the lancet needle ( 2 ) in the lancing direction through the lancet body ( 3 ). The lancet needle ( 2 ) is not laterally guided by the drive element ( 6 ). The lateral guidance is effected by the lancet body ( 3 ) or the composite of the individual lancet bodies ( 3 ).

For the lancet shape shown in FIG. 4, it has proven to be advantageous to choose a material that is so soft (with a Shore hardness A of 30 and less) for the lancet body ( 3 ), which also serves as sterile protection, that the lancet needle tip ( 5 ) due to its asymmetrical cut during the lancing movement, it does not deviate too much to the side and the friction forces during lancing are as low as possible (preferably less than 1N).

When the lancet needle tip ( 5 ) is encapsulated with the plastic of the lancet body ( 3 ), the geometry (shape) and the wall thickness of the encapsulation of the lancet needle tip ( 5 ) must be designed so that the lancet needle tip ( 5 ) can easily penetrate the plastic and the frictional forces Lancing is as small as possible (smaller than 2 N if possible).

FIG. 5 schematically shows another embodiment of the system according to the invention that is alternative to the embodiment of FIGS. 1 and 4. The partial figure 5A shows the conditions before and after the lancing process; Figure 5B shows the situation with the lancet ( 1 ) in the lancing position.

The lancet (1) or the lancet Association corresponds in Fig. 5 is essentially the embodiment of Fig. 4 contains the retraction device (7) in the embodiment shown here, a movable part (15) having a gripping device with a slot (9) for receiving the lancet ( 1 ). The movable part ( 15 ) is connected to a fixed part (not shown) of the return device ( 7 ) via a tension coil spring ( 16 ). During the lancing movement phase, during which the drive element ( 6 ) acts on the lancet ( 1 ), the spring ( 16 ) is stretched because the lancet ( 1 ) has the movable part ( 15 ) of the return device over its head ( 4 ) connected is. As soon as the power transmission through the drive element ( 6 ) has ended - that is, as soon as the lancet needle tip ( 5 ) has been fully extended for pricking - the tension spring ( 16 ) can return to its relaxed starting position. It takes the lancet needle ( 2 ) back into the starting position and, if necessary, also conveys the drive element ( 6 ) to the starting position.

An alternative embodiment of the system according to the invention is also shown schematically in FIG. 6. The lancet ( 1 ) corresponds essentially to the embodiment of FIG. 1. The partial figure 6A shows the conditions before and after the lancing process; Part FIG. 6B shows the situation with the lancet ( 1 ) in the lancing position, that is to say with the lancet needle tip ( 5 ) extended.

As in FIG. 5, the return device is formed from two mutually movable parts ( 14 , 15 ), one of which ( 14 ) is fixed and one ( 15 ) interacts with the lancet ( 1 ) during the lancing movement by moving the lancet ( 1 ) on her head ( 4 ), and is movable with it. The fixed part ( 14 ) contains a recess (hole) for the passage of the lancet needle tip ( 5 ). In contrast to FIG. 5, the return device ( 7 ) is supplemented in FIG. 6 by a compression coil spring ( 16 ) which is compressed when the lancing movement is carried out. As soon as the power transmission through the drive element ( 6 ) has ended - that is, as soon as the lancet needle tip ( 5 ) has been fully extended for pricking - the compression spring ( 16 ) can return to its relaxed starting position. It takes the lancet needle ( 2 ) back into the starting position and, if necessary, also conveys the drive element ( 6 ) to the starting position.

The embodiment shown in FIG. 6 contains on the side of the fixed part ( 14 ) of the return device ( 7 ) facing the lancet ( 1 ) a stop ( 23 ) for the lancet body ( 3 ) which prevents the lancet body ( 3 ) moved together with the lancet needle ( 2 ) during the lancing movement. This ensures that the tip ( 5 ) of the lancet needle ( 2 ) can move out of the body ( 3 ) and is thus available for the lancing process.

The embodiments of the inventive system in FIGS. 7 and 8, shown are variants of the embodiment of Fig. 6. Both Fig. 7 and Fig. 8 only show the starting position of the system. In both, the lancets ( 1 ) or the corresponding lancet assemblies from a plurality of lancets correspond to those from FIGS. 4 and 5. Since the lancets ( 1 ) are connected to one another here via webs ( 22 ), the lancet bodies ( 3 ) are fixed relative to one another effect, a stop ( 23 ) is unnecessary.

The fixed parts ( 14 ) of the return device ( 7 ) have alternative recesses in FIGS. 7 and 8 with respect to the embodiment of FIG. 6 (elongated slot in FIG. 7; parts separated by a gap in FIG. 8).

A further alternative embodiment of the system according to the invention is shown schematically in FIG. 9 ( FIG. 9A: before or after executing the lancing movement; FIG. 9B during the lancing process). The lancets ( 1 ) are moved here in a substantially circular manner around the return device ( 7 ). The lancets ( 1 ) or the corresponding lancet assemblies from a plurality of lancets essentially correspond to those from FIGS. 4 and 5. The drive principle corresponds to that from FIGS. 6 to 8: the lancets ( 1 ) are driven by a drive element ( 6 ) Rest position moved to the lancing position. The lancet ( 1 ) interacts with the movable part ( 15 ) of the return device ( 7 ) via its head ( 4 ). The movable part ( 15 ) moves towards the fixed part ( 14 ) and compresses a coil spring ( 16 ). The lancets ( 1 ) are laterally fixed in the area of the exposed needle ( 2 ) through cutouts ( 24 ) in the fixed and movable part ( 14 , 15 ) of the return device ( 7 ), which here have the shape of a ring gear, and are thus guided. The return device ( 7 ) has a ring provided with a recess, which serves as a stop ( 23 ) for the lancet bodies ( 3 ) and ensures that the lancet bodies ( 3 ) do not move together with the lancet needle ( 2 ) during the lancing movement.

The ring gear-shaped parts ( 14 , 15 ) of the return device ( 7 ) of this embodiment can also be used for the further transport of the lancets.

Fig. 10 shows, also in two sub-figures (Fig 10A: before and after carrying out the lancing movement; 10B during the lancing process..) A variant of the embodiment according to Fig 9. In contrast to the embodiment shown therein, the parts (14, 15. ) of the return device ( 7 ) no recesses. The guidance of the lancet needle ( 2 ) during the lancing process is accomplished here by the guide element ( 25 ) of the drive element ( 6 ).

FIG. 11 also shows two partial figures ( FIG. 11A: before or after performing the lancing movement; FIG. 11B during the lancing process) a variant of the embodiment according to FIG. 10. In contrast to the embodiment shown there, the guidance of the lancet needle ( 2nd ) here via a guide element ( 26 ), which can be fastened, for example, to a housing wall of a corresponding lancet magazine.

Of course, more or less than the lancets ( 1 ) shown can be contained in all the embodiments shown. It is also possible to interchange the different lancet shapes in the examples shown or to use lancets ( 1 ) other than the ones shown.

Claims (13)

1. System for storing and providing lancets for the extraction of body fluids, comprising

• a) a multiplicity of essentially needle-shaped lancets
• b) a drive unit which has a drive element which is moved from a rest position into a lancing position in order to carry out a lancing process;
• c) a storage area for storing the lancets;
• d) a removal area for leading at least the tip of a lancet out of the system during the lancing process; and
• e) a transport unit that can transport lancets from the storage area into the removal area,

wherein the drive element is arranged in such a way that it can act on the lancet located there in the removal area to carry out the lancing process and is thus moved from a rest position into a lancing position, and
the system in the removal area having a return device which can interact with the lancet located in the removal area in order to move the lancet from the lancing position into its rest position after the lancing process has been carried out. 2. The system of claim 1, wherein the lancet is at its opposite end End has a graspable element by the return device. 3. The system of claim 1, wherein the return device is a spring mechanism includes. 4. System according to any one of the preceding claims, wherein the lancets in one Magazine are housed. 5. The system of claim 4, wherein the retrieval device is included in the magazine is. 6. Method for temporarily extending the tip of a substantially needle-shaped one Lancet from a system for storing and providing lancets, one Drive element is moved from its rest position towards its lancing position and drives a lancet until it reaches its lancing position from its rest position  has reached, and then the lancet in its rest position with the help of a Return device is returned. 7. The method according to claim 6, wherein the return device in addition to the lancet the drive element moves in the direction of its rest position. 8. Lancet magazine for storing lancets, comprising

• a) a multiplicity of essentially needle-shaped lancets
• b) a storage area for storing the lancets; and
• c) a removal area for leading at least the tip of a lancet out of the magazine during the lancing process;

wherein the magazine either has a return device in the removal area, which can interact with the lancet, which is located in the removal area, to move the lancet from the lancing position to its rest position after the lancing process has been carried out, or has an engagement option for a return device. 9. lancet magazine according to claim 8, additionally containing

• a) a transport unit that can transport lancets from the storage area into the removal area.

10. lancet magazine according to claim 8 or 9, wherein the lancet at its tip opposite end a graspable element by the return device having. 11. lancet magazine according to claim 8, 9 or 10, wherein the return device Includes spring mechanism. 12. Lancing device suitable for use in a system for storing and providing lancets, comprising

• a) a drive unit which has a drive element which is moved from a rest position into a lancing position in order to carry out a lancing process;
• b) a storage area for storing lancets;
• c) a removal area for leading at least the tip of a lancet out of the system during the lancing process; and
• d) a transport unit that can transport lancets from the storage area into the removal area,

wherein the drive element is arranged in such a way that it can act on the lancet located there in the removal area to carry out the lancing process and is thus moved from a rest position into a lancing position, and
wherein the lancing device either has a return device in the removal area, which can interact with the lancet, which is located in the removal area, in order to move the lancet from the lancing position into its rest position after the lancing process has been carried out, or can take up a lancet magazine according to claim 8. 13. lancet ( 1 ) containing a lancet needle ( 2 ) and a lancet body ( 3 ) partially surrounding the lancet needle, suitable for use in a system according to one of claims 1 to 5.